Numerical Investigation of Thermofluid Characteristics of Shell-and-Plate Heat Exchangers – A Comparison with Plate Heat Exchangers

Three-dimensional numerical simulations are performed in order to examine the thermofluid characteristics of shell-and-plate heat exchangers. L, M, and H types of shell-and-plate heat exchangers with various chevron angles (45°/45°, 45°/65°, and 65°/65°) are studied in detail. The numerical simulations are in line with the experimental data. Results show that Nusselt number increases with the rise of chevron angle in plate side. This improvement is much pronounced at higher Reynolds numbers. However, the impact of chevron angle on the heat transfer performance in the shell side is reversed, i.e., the heat transfer performance declines with rise of chevron angle, especially at lower Reynolds numbers. Flow distribution along the plates and shell sides can be improved with larger chevron angles (65°/65°). Furthermore, the inlet and outlet manifold of the plate side are the main causes for maldistribution of fluid flow in the shell side. This is associated with the wake region and a diverted flow stream toward the edge of the shell. A dimensionless flow velocity is also proposed to characterize flow distribution and it is found to be independent of mass flow rate at a specified chevron angle. The resultant flow pattern between shell-and-plate heat exchanger and plate heat exchanger in high chevron angles is quite similar in the plate side.